JUST WATCHED

Homeowners cry as they return after fire

MUST WATCH

Homeowners cry as they return after fire02:08

Story highlights

Cal Fire says Atlas Fire containment is 45%, up from 3% a day before

36 killed in deadliest week of fires in state history

(CNN)Reinforcements from other regions are helping firefighters contain more of the largest wildfires devastating Northern California, though strong winds expected over the weekend could challenge those gains, a fire chief said Friday.

Meanwhile, officials are making grim discoveries -- victims burnt beyond recognition -- as they search blackened ruins of some of the 5,700 homes and business that have been destroyed.

"Some of (the remains) are merely ashes and bones," Sonoma County Sheriff Rob Giordano said at a Thursday evening news conference. "And we may never get truly confirmative identification on ashes. When you're cremated, you can't get an ID."

Thirty-six people have been killed since the wildfires began Sunday night, making this outbreak one of the deadliest in state history, according to the California Department of Forestry and Fire Protection (Cal Fire).

Photos:Wildfires blaze in California

Aerial images showing parts of Sonoma and Napa County that have been hit by wildfires.

Hide Caption

1 of 33

Photos:Wildfires blaze in California

Colby Clark, left, comforts her mother, Bonnie Trexler, after law enforcement escorted them to Trexler's home in Napa, California, to retrieve medicine and personal items on Wednesday, October 11. Trexler was one of the lucky few in her neighborhood whose home was spared. Deadly wildfires have been tearing through the state, destroying homes and businesses and prompting evacuation orders.

Hide Caption

2 of 33

Photos:Wildfires blaze in California

Highway Patrol officers go door to door to ask Sonoma residents to evacuate their homes as a wildfire approaches on October 11.

Hide Caption

3 of 33

Photos:Wildfires blaze in California

Homes are destroyed in the Coffey Park neighborhood of Santa Rosa on October 11.

Hide Caption

4 of 33

Photos:Wildfires blaze in California

The sign of a Firestone store malfunctions in Santa Rosa on Tuesday, October 10.

Hide Caption

5 of 33

Photos:Wildfires blaze in California

Damaged winemaking vats and tanks stand in ashes and debris at the Paradise Ridge Winery in Santa Rosa.

Hide Caption

6 of 33

Photos:Wildfires blaze in California

Smoke clouds the sun from wildfires burning in Santa Rosa and Napa Valley on October 10.

Hide Caption

7 of 33

Photos:Wildfires blaze in California

Mary Caughey, center in blue, reacts after finding her wedding ring in the remains of her home in Kenwood on October 10.

Hide Caption

8 of 33

Photos:Wildfires blaze in California

Puddles of melted metal trail away from a burned-out car near Napa on October 10.

Hide Caption

9 of 33

Photos:Wildfires blaze in California

A TV cameraman inches closer to a burning building at a winery in Napa Valley on Monday, October 9.

Hide Caption

10 of 33

Photos:Wildfires blaze in California

A firefighting plane helps battle a blaze just north of Tustin on October 9.

Hide Caption

11 of 33

Photos:Wildfires blaze in California

A historic barn burns in Santa Rosa on October 9.

Hide Caption

12 of 33

Photos:Wildfires blaze in California

The Santa Rosa Hilton Hotel burns to the ground on October 9.

Hide Caption

13 of 33

Photos:Wildfires blaze in California

Jim Stites watches as part of his neighborhood burns in Fountaingrove on October 9.

Hide Caption

14 of 33

Photos:Wildfires blaze in California

Fire burns from an open gas valve near the pool area of a Santa Rosa trailer park on October 9.

Hide Caption

15 of 33

Photos:Wildfires blaze in California

A man rushes to save his house as a wildfire moves through Glen Ellen on October 9.

Hide Caption

16 of 33

Photos:Wildfires blaze in California

Kristine Pond searches what's left of her family's home in Santa Rosa on October 9.

A woman moves horses in Orange as strong Santa Ana winds blow smoke from the Canyon 2 fire toward them on October 9.

Hide Caption

20 of 33

Photos:Wildfires blaze in California

A firefighter douses flames at a home in Anaheim on October 9.

Hide Caption

21 of 33

Photos:Wildfires blaze in California

Traffic backs up as people flee Orange on October 9.

Hide Caption

22 of 33

Photos:Wildfires blaze in California

Santa Rosa residents sift through the remains of a burned home on October 9.

Hide Caption

23 of 33

Photos:Wildfires blaze in California

The remains of fire-damaged homes and cars smolder at a Santa Rosa trailer park on October 9.

Hide Caption

24 of 33

Photos:Wildfires blaze in California

A tent structure built for the Safeway Open golf tournament burns in Napa on October 9.

Hide Caption

25 of 33

Photos:Wildfires blaze in California

Fire consumes a barn in Glen Ellen on October 9.

Hide Caption

26 of 33

Photos:Wildfires blaze in California

Smoke rises in the hills east of Napa on October 9.

Hide Caption

27 of 33

Photos:Wildfires blaze in California

A man passes a burning house in Napa on October 9.

Hide Caption

28 of 33

Photos:Wildfires blaze in California

The remains of fire-damaged homes are seen in Glen Ellen on October 9.

Hide Caption

29 of 33

Photos:Wildfires blaze in California

A wildfire burns behind the Sonoma Raceway on October 9.

Hide Caption

30 of 33

Photos:Wildfires blaze in California

A building burns in Napa on October 9.

Hide Caption

31 of 33

Photos:Wildfires blaze in California

Flames overtake a building in the Napa wine region on October 9.

Hide Caption

32 of 33

Photos:Wildfires blaze in California

Two women hug as they watch houses burn in Santa Rosa on October 9.

Hide Caption

33 of 33

Firefighters are making progress on some of the bigger fires, Napa County Fire Chief Barry Biermann said Friday, thanks in large part to the gumption of those who've been on the lines for days and the reinforcements who are relieving them.

Read More

"It's like pulling teeth to get law enforcement and firefighters to disengage from what they're doing out there -- they're truly passionate about what they're doing to help the public. But the reinforcements are coming in, and that's why you're seeing the progress that we're making," Biermann said.

Since Sunday, the deadly fires haveconsumed thousands of homes and forced evacuations in Northern California's wine country and produced unhealthy air quality in the San Francisco Bay Area.

Though progress has been made on the big fires, much more work is ahead.

The 48,000-plus acre Atlas fire in Napa and Solano counties was 45% contained Friday -- up from 3% the day earlier. The 44,000-acre Nuns fire in Sonoma County -- an amalgamation of three recently merged fires north and west of Glen Ellen -- was 5% contained.

Latest developments

• Of the 36 people who were killed by the fires since Sunday night, 19 died in Sonoma County, officials said. Nine people in Mendocino County, at least four in Yuba County and four in Napa County have died, officials said.

• More than 2,800 residences in Santa Rosa have been destroyed by wildfires, Mayor Chris Coursey said. The number of destroyed structures in the state went up Friday by 2,200 to 5,700, Cal Fire said.

• Winds could be especially gusty Friday night through Saturday. Those conditions, joined with low humidity, could spread the flames drastically, the National Weather Service warns. "Very dangerous #fire conditions expected overnight (Friday) due to strong winds and ongoing fires. Please be prepared & aware!" the weather service tweeted.

• The causes of the fires are under investigation. But officials said their spread was aided by strong winds Sunday night, with some gusts of more than 70 mph.

• About 34,000 utility customers are without electricity service -- and natural gas service to 47,000 customers has been shut off -- mostly in Sonoma and Napa counties, the Pacific Gas and Electric Co. said Friday.

Searchers look for human remains in a Santa Rosa mobile home community.

Sonoma, Mendocino and Napa counties have been among the hardest hit by the fires. Nearly 20% of the population in those counties is over 65, according to US Census Bureau data.

In Sonoma, authorities had to turn to dental records, fingerprints, tattoos and serial numbers on hip implants to identify victims.

"We've been forced to work that direction because we may not have enough information to identify people because of the ... severity of the burn," Giordano said.

On Friday, cadaver dogs and searchers went through what was left of a mobile home park in Santa Rosa.

"We start with a bedroom because this fire occurred at night we think a lot of people were in their bedrooms," said Sonoma County Sheriff's spokesman Spencer Crum told CNN affiliate KOVR of Sacramento.

There were about 300 mobile homes in the neighborhood.

Pregnant woman flees on bike

Evacuees who escaped oncoming flames described harrowing ordeals.

Charity Ruiz, who is pregnant, had been in a car with her family trying to evacuate from their Santa Rosa neighborhood but got stuck in a traffic jam.

"Honestly, I've never in my life felt like I was going to die like that moment," Ruiz told CNN affiliate KPIX. "Not just me, but my girls and unborn baby."

Unable to wait any longer, Ruiz walked back and got her bike from her house and rode out of the neighborhood with her two girls in the toddler trailer.

"I can ride a bike, but I'm pregnant so it was hard," she told the station. Ruiz had been scheduled to have her baby next week.

She and her kids made it out of harm's way, but their home burned to the ground.

'Peanuts' creator's home lost to wildfire

The fires have been fast and ruthless, shifting without much notice and destroying thousands of structures.

His widow, Jean, 78, evacuated from the home Monday, shortly before the flames reduced it to rubble, his son Monte Schulz said. The fire destroyed precious reminders of the life his stepmother and his late father had built together, along with memorabilia, Schulz told CNN.

Victims ponder next moves

Many who lost homes are trying to figure out what to do next. In Yuba County, where a 10,000-acre blaze has killed at least four people, Mariano and Christa Domingo saw the fire approach their fence Sunday night, and they drove away with only one emergency oxygen tank for Christa, who has lung problems, CNN affiliate KOVR reported.

"She was thinking we had to pack up things, and I said, 'No, we don't have any time,' " her husband told the TV station.

Their house was destroyed, and the couple only have clothes they received from a shelter. They said they intend to rebuild their home.